Efficient loading of cargo on a transportation or delivery vehicle is one of the most effective measures to improve the delivery efficiency of the vehicle. For loading cargo into the vehicle as effectively as possible, it is necessary to learn the cargo loading performance of the vehicle as well as an unused or waste space in the luggage compartment. To acquire the loading performance, there has been well known a method in which a loading operator or a driver who loads cargo onto the vehicle makes a record of loading conditions of the vehicle.